Rapidly drying lower aliphatic alcohol-acetone sanitizing composition and method



3,445,564 RAPIDLY DRYING LOWER ALIPHATIC ALCOHOL- No Drawing. Filed Jan.4, 1965, Ser. No. 428,007 Int. Cl. A61k 27/00, 9/00 U.S. Cl. 424-45 6Claims ABSTRACT OF THE DISCLOSURE A method, compositions and articlesfor sanitizing public or communal facilities prior to individual use aredescribed. The method consists of applying a thin layer of a rapidlydrying liquid germicidal composition to a surface, such as a toiletseat, and drying the surface prior to use. The rapidly drying germidicalcompositions consist essentially of a lower aliphatic alcohol and atleast about of a volatilizing agent therefor, such as acetone. Thearticles of the invention are dispensing units containing the germicidalcompositions, including aerosol and other spray units and otherdispensing devices capable of applying a thin layer of the germicidalcompositions to a surface to be sanitized.

The present invention relates to a sanitizing method and to articlesuseful therein and, more particularly, to a method and articles adaptedfor use by an individual member of the public at large to sanitize ordisinfect public or communal facilities prior to use by the individual.

Many people are reluctant, for sanitary or aesthetic reasons, to usefacilities or objects of personal use previously employed by others. Forthis reason various expedients have been suggested for achievingsanitary use public facilities such at toilet seats. For example,devices have been developed for exposing toilet seats to germicidalultraviolet radiation after use thus assuring subsequent users of thesanitary condition of the toilet seat. Another common expedient is toprovide a supply of disposable single-use paper toilet seat covers at alocation adjacent to the toilet seat. While both of these expedients arein current use to some extent, they are not universally available and,therefore, fail to provide a satisfactory solution to the problem.

Therefore, it is a primary object of the invention to providesconvenient means for individuals to sanitize public facilities such astoilet seats and other articles and surfaces prior to personal use.

It is another object of the invention to provide articles adapted to becarried customarily by an individual for use in sanitizing publicfacilities such as toilet seats and other articles or surfaces prior touse.

It is still another object of the invention to provide a purse or pockestize aerosol dispenser containing a rapidly drying liquid germicidalcomposition.

The above and other objects of the invention which will be apparent fromthe detailed description herein are achieved by providing as novelarticles, conveniently carried purse or pocket size dispenserscontaining a rapidly drying liquid germicidal composition consistingessentially of a lower aliphatic alcohol and a volatilizing agent. Themethod of the invention comprises applying a rapidly drying germicidalcomposition to a surface to be sanitized such as a toilet seat, forexample, .and then drying the treated surface prior to personal use.

More specifically, the method of the invention is carried out byapplying a rapidly drying liquid germicide to the surface to be treatedby any suitable technique such as Patented May 20, 1969 spraying, rollercoating, brushing, wiping, sprinkling or the like. The spray techniqueis preferred because of its convenience and efliciency. Any type ofspray applicator may be employed although it is, of course, preferred touse the simplest and least cumbersome equipment possible. For thisreason, aerosol spray dispensers are especially suitable althoughconventional atomizers are also convenient to use.

Other useful germicidal applicators include cans, jars or tubes closedat one end by means of a spherical applicator mounted for rotation. Whenthe applicator is rolled over a surface liquid is transferred from thecontainer to the surface. The rapidly rying liquid germicide may also beconveniently applied by means of a saturated pad of cellulosic or othermaterial which is individually packaged in a. sealed metal foilcontainer. The foil container is adapted to be opened by tearing so thatthe gerimicide-moistened pad can be removed and wiped over the surfaceof the toilet seat. Still another suitable application technique is tosprinkle the toilet seat, for example, with germicide from a suitablecontainer followed by wiping the seat with toilet tissue to spread thegermicide evenly and thinly over the surface of the seat. Innumerableother suitable application techniques will suggest themselves to thoseskilled in the art.

The second step of the method of the invention, i.e. drying of theliquid germicide on the treated surface, is greatly facilitated by theuse of a germicidal composition compounded for spontaneous and rapidevaporation. Suitable compositions for this purpose will be describedbelow. Drying of the treated surface may also be facilitated byminimizing the amount of germicide applied in step one and by achievinguniform distribution of the germicide over the surface to be treated.The thickness of the layer of applied germicide may be reduced, thushastening drying, by wiping the treated surface with toilet tissue orany other suitable material. Wiping of the surface also promotesuniformity of coverage and serves to remove soil and any excessgermicide applied in step one. Any

, other suitable technique for drying the treated surface may also beemployed.

The fast drying liquid germicidal compositions employed according to thepresent invention in sanitizing toilet seats and other articles andsurfaces consist essentially of a lower aliphatic alcohol and avolatilizing agent. Although other optional materials may also beincluded such as additional antibacterial agents, perfume, propellantsand the like.

Suitable lower aliphatic alcohols for use in the germicidal compositionsinclude methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropylalcohol and the butyl alcohols. Ethyl alcohol, while otherwise highlysatisfactory, has the disadvantage of being high in cost. The butylalcohols, while useful, are less satisfactory because of their highermolecular weight and consequent higher boiling points and lowervolatility which tends to increase the drying time of the germicidalcompositions. For these reasons isopropyl alcohol is the material ofchoice since it has excellent germicidal activity, is low in cost,readily available, and sufficiently volatile to give a satisfactorydrying rate when blended with suitable proportions of a volatilizingagent.

Inasmuch as the lower aliphatic alcohols are not sufficiently volatileto afford usefully short drying times for practical purposes in themethod and articles of the present invention it is necessary to includea volatilizing agent in the germicidal composition. Suitable materialsfor this purpose include but are not limited to volatile organic liquidsmiscible with lower aliphatic alcohols including the lower molecularWeight alkanes, ketones, ethers and alkyl halides, for example. Morespecifically suitable volatilizing agents include the pentanes andhexanes, acetone, methyl ethyl ketone, dimethyl ether, methyl ethylether, methyl chloride, ethyl chloride, the propyl chlorides, methylbromide, ethyl bromide and the propyl bromides among others Which willbe readily apparent to those skilled in the art.

The proportion of volatilizing agent to lower aliphatic alcohol in therapidly drying germicidal compositions employed in the invention mayvary widely depending upon a number of factors, which include amongothers, the volatility of the alcohol employed, the volatility of thevolatilizing agent, the desired drying rate of the germicidalcomposition, the amount of germicidal agent applied to the surface to betreated and the method of application of the germicide, not to mentionthe prevailing conditions of temperature and relative humidity underwhich the product is to be employed. In general, however, it can bestated that the germicidal compositions must contain at least about 5%of volatilizing agent by volume based upon to the total volume ofvolatilizing agent and aliphatic alcohol in the composition. Althoughless than 5% of volatilizing agent may be employed with advantage insome cases, e.g. as little as 1% or even less, the reduction in dryingrate achieved at such levels is generally insufficient for practicalpurposes with most compositions. At the other end of the range, as muchas about 80% or more volatilizing agent by volume may be employed basedupon the volume of the alcohol-volatilizing agent mixture. It is notgenerally necessary, however, to employ such large volumes ofvolatilizing agent.

to achieve a satisfactory drying rate. Moreover, it is generallydesirable to minimize the amount of volatilizing agent employed in orderto avoid unnecessary dilution of the germicidal alcohol although this isnot a serious consideration where the volatilizing agent is also activeagainst germs as has been found to be the case with acetone. Therefore,it is preferred to employ about to 40% of volatilizing agent by volumebased on the total volume of the alcohol-volatilizing agent mixture,depending upon the various factors noted above. Of course, relativelylarge amounts of volatilizing agent are required to achieve a givendrying rate with the higher molecular weight alcohols and with methodsof application which are less efiicient in providing a uniform layer ofminimal thickness on the surface to be sanitized. Conversely smalleramounts of volatilizing agent are required with the more volatile lowermolecular weight alcohols and when a minimal amount of germicidalcomposition is applied to the surface to be sanitized in a uniform layerof minimal thickness.

More specifically, an excellent and novel germicidal composition for usein the present invention consists essentially of an isopropylalcohol-acetone mixture, the acetone volatilizing agent being present inabout 15 to 40% and preferably about by volume based upon the volume ofthe alcohol-acetone mixture.

As noted above, the amount of volatilizing agent employed depends uponthe drying rate desired. Although suitable drying rates for a thin layerof germicidal composition on a surface to be sanitized may vary widelyit is obviously desirable to maximize this rate in order to minimizewaiting time before the sanitized surface may be used. Therefore, it isgenerally desirable to employ a germicidal composition having a dryingrate such that a thin uniform layer spread on a surface will dryspontaneously in about 1 minute and preferably in less than secs.Compositions having a drying rate such that a thin layer would requireseveral minutes or even more to dry may also be used, however,particularly if they are intended for only occasional use or for use tosanitize surfaces which are not expected to be put to immediate use.

Where inherently less rapidly drying compositions are employed, the timerequired to achieve a dry sanitized surface may be materially shortenedby wiping the wetted surface with a suitable material which ispreferably but Example I A typical rapidly drying liquid germicidalcomposition is made by mixing the following substances:

Amount per Percent by volume based Component unit charge, on totalvolume or ml. alcohol-acetone mixture Isopropyl alcohol 22. 5 Acetone 7.5 25 Perfume 06 0. 2

Mixing may be accomplished by any suitable conventional means, noproblem being encountered since the acetone and alcohol are completelymiscible. The unit charge of germicidal liquid obtained in this way isthen packaged in a conventional aerosol container of suitable size bywell known procedures with the addition of about 46% by weight of Freon12 (CCl F as a propellant, based upon the weight of the totalalcohol-acetone, Freon perfume composition.

When an aerosol container charged with the above germicidal compositionand propellant is used to spray a surface to be sanitized such as atoilet seat, a thin uniform layer of germicide may be obtained whichdries spontaneously by evaporation in less than 1 minute. If the sprayedsurface is wiped with toilet paper immediately after spraying the dryingprocess is accelerated so that the treated surface dries completely in afew seconds.

The aerosol germicidal spray dispenser of Example I when used asdescribed therein provides a convenient and expeditious means ofsanitizing any desired surface not attacked by alcohol or acetone suchas the seat of a public toilet.

The novel rapidly drying liquid germicidal composition of Example I mayalso be applied to the surface to be treated by other suitabletechniques in carrying out the method of the invention, such as by theuse of an atomizer, sprinkler, applicator pad or the like.

The preferred method of applying the germicidal composition, however, isby the use of a pressurized spray technique. Any suitable propellant maybe used for the germicidal composition including the preferred Freontype fiuorinated chlorohydrocarbons, of which representative members aremonochlorodifluoromethane (CHClFg), dichlorodifl-uoromethane (CCl Fmonochlorodifiuoroethane (CH CClF octafiuorocyclobutane (C Fdichlorotetrafiuoroethane (CC1F CC1F dichlorofluoromethane (CHCl F),trichlorofluoromethane (CC1 F); chlorinated hydrocarbons such as ethylchloride and methylene chloride among others; alkanes such as propaneand butane among others; other volatile organic compounds such asdimethyl ether; and compressed gases such as nitrous oxide, carbondioxide, nitrogen and argon, as well as compatible mixtures of the aboveand other propellants. The chemical identity of the propellant employedis not critical in the method and articles of the present invention withthe exception that the propellant must not have a sufficientlydeleterious effect on the germicidal composition employed to destroy itsutility as a germicide.

The propellant may be soluble or insoluble in the germicidalcomposition. The ratio of the propellant to germicidal composition mayvary widely and will depend upon many factors including the compositionof the germicidal mixture, the physical characteristics of thepropellant, the

size and geometry of the aerosol or other spray device and the degree towhich it is filled, all as well known in the art.

It has been found, however, that it is generally necessary to employsufficient propellant to produce an internal pressure in the containerof at least about 15 pounds per square inch gauge (p.s.i.g.) in order toachieve satisfactory application of the germicide to a surface to besanitized. Any reasonable pressure above 15 p.s.i.g. may be employed,limited only by the bursting strength of the container and safe use ofthe spray. It has been found, however, that pressures of about 15 to 70psig are suitable and entirely adequate for most purposes.

dispenser of Example I and allowed to stand for a short period and theneach slide was aseptically transferred to 50 mls. of Letheen brothsubculture media. Thirty minutes after the initial transfer, the slideswere re-transferred to a fresh subculture.

The primary and secondary subcultures of Salmonella choleraesuis andStaphylococcus aureus were incubated for 48 hours at 37 C. and theprimary and secondary subcultures of Trichophyton interdigita'le wereincubated for ten days at 28 C., after which they were examined forgrowth or no growth of the test organism. The results of these tests aresummarized in Table I below.

TABLE I Spray T Dist Subculture series No.

me ance, Sample sec: inches Organism 1 2 3 4 5 6 7 8 9 10 3 4Disinfectant aerosol spray of ExampleI g i ggggggfgggggf i gk 3 3Staphylococcus aureus 2 2 g }Trzch0ph1 ttminterdzgztale. 1.507- 0 g}Salmonella choleraesmr 2.00 n 125% 3 3 }Staphylococcusaureus....

Inasmuch as it is a primary object of the invention to provide aconveniently carried germicide dispenser the container must be compactin size. This influences the choice of a desirable propellant in view ofBoyles law which states that at a constant temperature, the pressure ofa given quantity of gas is inversely proportional to the volume itoccupies. Inasmuch as the temperature and volume of the propellant gasare constant for a dispenser of any given size, reduction of the amountof gas in the container by spraying causes a rapid drop in the gaspressure. Therefore, when gases such as nitrogen, carbon dioxide, argonand the like are used in small aerosol containers, the pressure drops sorapidly on use that it may fall below p.s.i.g. before the container hasbeen emptied of germicide. The Freon type liquid fiuorinatedchlorohydrocarbon propellants are preferred, therefore, since theymaintain a relatively constant pressure above the germicide in thecontainer as long as any of the propellant remains in the liquid phase.This is due to the fact that the Freon type propellants and othervolatile liquid propellants vaporize to replace vapor lost in sprayingthus repeatedly restoring the vapor pressure in the container as long asthe supply of liquid propellant lasts.

The aerosol spray product of Example I was tested against therepresentative organisms T richophyton interdigitale, a fungus, andSalmonella choleraesuis and Staphylococcus aureus, bacteria. Thegermicidal activity of the isopropyl alcohol-acetone mixture wascompared to that of phenol according to the method described in theJournal of the A.O.A.C., vol. 44, No. 1, pages 137-138 (1961). Ninety(90) one inch glass slides were sterilized. Under aseptic conditions,0.01 ml. of a separate 48 hour culture of each of the above organismswere spread over 30 of the sterile slides which were then dried for 30minutes at 37 C. After drying, of the slides in each group were sprayedwith dilutions of phenol for 3 seconds at a distance of 3 inches asfollows:

Trichophyton interdigitale-Ten (l0) slides were sprayed with a 1.50%solution of phenol and ten 10) slides were sprayed with a 1.00%solution.

Salmonella choleraesuisTen (l0) slides were sprayed with a 1.50%solution of phenol and ten (10) slides were sprayed with a .50%solution.

Staphylococcus aureus-Ten (l0) slides were sprayed with a 2.00% solutionof phenol and ten (10) slides were sprayed with a 1.25% solution.

The remaining 10 slides in each group were sprayed at a distance of 4inches for 3 seconds with the aerosol spray It is apparent from the datain Table I above that the germicidal aerosol spray and sanitizing methodof Example I are highly effective as illustrated by their bactericidaland fungicidal activity against representative organisms.

It will be apparent from the foregoing that the method and articles ofthe present invention provide for the first time convenient means for anindividual to sanitize a toilet seat or other article or surface priorto personal use.

The novel germicidal compositions of the present invention consistingessentially of isopropyl alcohol and at least about 5% by volume ofacetone, have unexpected utility as sanitizing agents. This is due tothe fact that although the antiseptic properties of isopropyl alcoholare Well known, the germicidal activity of acetone and its mixtures withisopropyl alcohol had not been discovered heretofore. The antibacterialand antifungal activity of isopropyl alcohol-acetone mixtures containing25% to or more acetone by volume is especially surprising since as notedabove the teachings of the prior art would suggest that dilution of theisopropyl alcohol to this extent would materially reduce germicidalactivity. As may be seen from the data in Table I above, this is not aserious problem when the diluent is acetone as shown by the excellentgermicidal activity of the 25 acetone mixture against representativeorganisms.

It should be noted, furthermore, that the isopropylalcohol-acetonemixtures of the present invention differ from many germicides commonlyused heretofore in that they are essentially nonaqueous in character.This is important, although not absolutely essential, in the method ofthe present invention since water tends to delay drying of the germicidewhen applied to a surface to be sanitized. Although essentiallynonaqueous, small amounts of water may be tolerated in the isopropylalcohol-acetone compositions. Therefore, the readily available constantboiling isopropyl alcohol-water mixture which contains about 13.3 watermay be employed in formulating the alcoholacetone germicidalcompositions since the proportion of water thus derived does notseriously retard the drying rate of the compositions.

Although the isopropyl alcohol-acetone compositions of the presentinvention have excellent germicidal activity in that bacteria, fungi andother lower organisms are killed on contact within seconds, if desired,additional antibacterial, antifungal or other active ingredients may beincorporated in these or other rapidly drying liquid germicidalcompositions useful in the invention. Suitable germi cidal additivesinclude the well known anti-bacterial quaternary ammonium compounds suchas cetyl pyridinium chloride and benzalkonium chloride and other knowngermicidal agents such as hexachlorophene, for example.

Any suitable perfume may be employed in quantities sufiicient to givethe germicide a pleasant odor and/ or to mask unpleasant odors in theenvironment of use.

The preferred germicidal compositions of the invention consistpredominantly of lower aliphatic alcohol and volatilizing agent, i.e.these ingredients make up about 85 to 100% of the liquid content of thecompositions exclusive of any liquid propellant employed. As notedabove, however, the compositions may also contain water or other usualimpurities associated with the alcohol or volatilizing agent, addedgermicidal agents, perfume etc. If desired the germicidal compositionsmay be diluted with inert liquids such as water or hydrocarbon solventsmiscible with the active alcohol and volatilizing agent. Up to 90% ofsuch inert liquids may be employed if desired but in this case theamount of volatilizing agent recited above should be based on the totalvolume of liquid including the inert liquid rather than on the volume ofthe alcoholvolatilizing mixture.

I claim:

1. An aerosol spray dispensing unit containing a rapid ly drying liquidgermicidal composition and a propellant therefor, said unit beingadapted to apply a thin uniform layer of said germicidal composition toa surface to be sanitized, said liquid germicidal composition consistingof a lower alkyl alcohol havng 1 to 4 carbon atoms and from about 5 to80 percent by volume of acetone as the active ingredients, said acetonealso acting as a volatilizing agent for said composition.

2. An aerosol spray dispensing unit according to claim 1, wherein saidliquid germicidal composition contains about to 40 percent acetone byvolume.

3. An aerosol spray dispensing unit according to claim 1, wherein saidliquid germicidal composition contains about 25 percent acetone byvolume.

4. A method for sanitizing a surface prior to personal use whichcomprises applying to said surface a thin uniform layer of the rapidlydrying liquid germicidal composition of claim 1 and drying said surfaceto provide a dry sanitary surface for personal use.

5. A rapidly drying liquid germicidal composition consisting ofisopropyl alcohol, about 25 percent by volume of acetone and anantibacterial substance selected from the group consisting ofhexachlorophene and a quaternary ammonium compound.

6. An aerosol spray dispensing unit containing a rapidly drying liquidgermicidal composition and a propellant therefor, said unit beingadapted to apply a thin uniform layer of said germicidal composition toa surface to be sanitized, said liquid germicidal composition consistingof a lower alkyl alcohol having 1 to 4 carbon atoms, from 5 to percentby volume of acetone and an antibacterial substance selected from thegroup consisting of hexachlorophene and a quaternary ammonium compound.

References Cited OTHER REFERENCES Reddish: Antiseptics, Disinfectants,Fungicides, and Chemical and Physical Sterilization, Lea & Febiger,Philadelphia (1954), pp. 298301 and 3043 14.

Shephard: Aerosols-Science and Technology, Interscience Publishers, NewYork (1961), pp. 203, 221, 228, 233, 344-346, 464 and 514.

The Canadian Patent Otfice Record, Nov. 18, 1941, p. 3238, No. 400, 785.

ALBERT T. MEYERS, Primary Examiner.

V. C. CLARKE, Assistant Examiner.

U.S. Cl. X.R.

